Rodents & Pests

Rats, mice, mosquitoes, ticks and fleas can all carry serious diseases. Other pests, such as cockroaches and bed bugs, can be serious nuisances.

The Snohomish Health District provides information on the control of rats and insects, known as “vectors.” We also respond to complaints and can assist neighborhoods when rodent infestations or other problems pose a public health risk.

Hantavirus

The deer mouse is the main carrier of hantavirus in the western United States. Deer mice are most common in rural settings, but live in all parts of Washington. A person may be exposed to hantavirus by breathing contaminated dust after disturbing or cleaning rodent droppings or nests, or by living or working in rodent-infested settings.

Typically one to five cases of hantavirus are reported each year in Washington state. Hospital care is usually required and this rare disease can be fatal.

The best way to avoid exposure to hantavirus is to carefully clean up rodent droppings, prevent rodent infestations, and avoid wild rodents.

Controlling bed bugs

Bed bugs are small, flat insects that feed on your blood, typically at night, while you are sleeping. Unlike most public health pests, bed bugs are not known to transmit or spread disease.

However, some people are more sensitive to the bites and develop itchy, red welts. Scratching the bites can lead to infection. Bed bugs may also affect a person's mental health, causing anxiety, insomnia, and irritability.

Experts believe the recent increase in bed bugs in the United States may be due to more travel, lack of knowledge about preventing infestations, increased resistance of bed bugs to pesticides, and ineffective pest control practices.

Bed bug infestations can be difficult to control, but don't resort to improperly using pesticides such as foggers or “bug bombs.” Serious health risks can occur.

Killing cockroaches

Cockroaches are less common in Washington than in crowded cities and the southern regions of the United States. However, where cockroaches are present, their droppings and leftovers can be a significant trigger for asthma in humans. Make sure that you kill cockroaches safely, so that humans and animals aren't hurt.

Pest control is an important part of routine Food Safety inspections by Snohomish Health District. The health inspectors work with food establishment operators to implement pest control maintenance plans.

Mosquitoes and West Nile Virus

West Nile virus is rare in Washington State, with only 1 reported human case in 2013. The virus is spread by the bite of infected mosquitoes. Mosquitoes that tested positive for the virus were found in six counties last year (Benton, Franklin, Grant, Skagit, Yakima, and Spokane).

Birds in the crow family are susceptible to West Nile virus and can provide an early warning of virus activity. The state Department of Health asks people to report dead birds using its online dead bird reporting system. Crows, ravens, jays, magpies, and hawks are particularly important to report because they often die from West Nile virus infection.

Snohomish Health District collected hundreds of birds and mosquito samples between 2002 and 2007. Only one virus-positive bird was found in 2002, and two birds with West Nile were found in 2006. The local surveillance program was discontinued in 2008.